Question

1. In a study of speed​ dating, male subjects were asked to rate the attractiveness of their female​ dates, and a sample of the results is listed below ​(1equals=not ​attractive; 10equals=extremely ​attractive). Construct a confidence interval using a 99% confidence level. What do the results tell about the mean attractiveness ratings of the population of all adult​ females? 6​, 8​, 1​, 10​, 7​, 5​, 8​, 9​, 7​, 10​, 3​, 9 What is the confidence interval for the population mean muμ​?

2.An IQ test is designed so that the mean is 100 and the standard deviation is 24 for the population of normal adults. Find the sample size necessary to estimate the mean IQ score of statistics students such that it can be said with 95​% confidence that the sample mean is within 4 IQ points of the true mean. Assume that σ=4 and determine the required sample size using technology. Then determine if this is a reasonable sample size for a real world calculation. The required sample size is

3.The ages of a group of 158 randomly selected adult females have a standard deviation of 17.5 years. Assume that the ages of female statistics students have less variation than ages of females in the general​ population, so let σ=17.5 years for the sample size calculation. How many female statistics student ages must be obtained in order to estimate the mean age of all female statistics​ students? Assume that we want 95​% confidence that the sample mean is within​ one-half year of the population mean. Does it seem reasonable to assume that the ages of female statistics students have less variation than ages of females in the general​ population?

4.Salaries of 45 college graduates who took a statistics course in college have a​ mean 68,400. Assuming a standard​ deviation 16 238​, construct a 90​% confidence interval for estimating the population mean muμ.